By the common law, all mines of gold and silver belonged to the king, and also, it seems, all mines in which gold or silver might be found in connection with other metals.38 It was, however, enacted by statute in England that no copper, tin, iron, or lead mine should be a royal mine merely because gold and silver were taken therefrom.39 The question whether the common-law rule is in force in this country is of little importance, owing to the fact that the precious metals have been found almost exclusively in the public domain of the United States, and the rights of the finders and workers thereof are secured by express legislation on the subject.40 In one case, however, it has been decided not to be in force so as to vest the title to a gold or silver mine in the state, on the ground that the rights of the crown at common law were personal to the reigning monarch, and not attributes of sovereignty.41